Discussion about HPS To LED Conversions

[ButterflyEffect]

I've been toying with the idea of swapping my 3 flower rooms over to LED. I currently run CMH setups.

My situation is a bit more complex. I not only would consider a switch to LED to save lamp power but also A/C costs. Add to that, I'd also like to go from vertical to horizontal. Right now the amount of labor in screening/descreening my plants is huge. If I could do it and get similar quantity and quality, I'd do it for the labor savings alone.

I'm just having a tough time trying to evaluate the lamps for coverage. PPF maps seem to be all over the place and even outside of that, how do I know what wattage lamp setup is enough? Or too much?

I think I'll at least start by replacing my T5 in Veg with an LED unit and see how it performs.

 

[GoatCheese]

I've been toying with the idea of swapping my 3 flower rooms over to LED. I currently run CMH setups.

My situation is a bit more complex. I not only would consider a switch to LED to save lamp power but also A/C costs. Add to that, I'd also like to go from vertical to horizontal. Right now the amount of labor in screening/descreening my plants is huge. If I could do it and get similar quantity and quality, I'd do it for the labor savings alone.

I'm just having a tough time trying to evaluate the lamps for coverage. PPF maps seem to be all over the place and even outside of that, how do I know what wattage lamp setup is enough? Or too much?

I think I'll at least start by replacing my T5 in Veg with an LED unit and see how it performs.

It think you should look at lights around 400-600 watt range, something that will give you alot of foot print coverage like the new multi-bar lights from Mars Hydro and some others. You always want dimmers on your lights to suit different sized plants

Imo, the 800 watt led light talked about earlier is huge over kill for most rooms.
Is it efficient? It’s alot of watts for a relatively small foot print. Maybe two 400 watters would be better in most cases than one of those 800 watt leds.

Buy few lights at first to get a better idea how to the get most out of them and to get an idea how powerful lights are best suited for your rooms.

 

[ButterflyEffect]

It think you should look at lights around 400-600 watt range, something that will give you alot of foot print coverage like the new multi-bar lights from Mars Hydro and some others. You always want dimmers on your lights to suit different sized plants

Imo, the 800 watt led light talked about earlier is huge over kill for most rooms.
Is it efficient? It’s alot of watts for a relatively small foot print. Maybe two 400 watters would be better in most cases than one of those 800 watt leds.

Buy few lights at first to get a better idea how to the get most out of them and to get an idea how powerful lights are best suited for your rooms.

Thanks. Yeah, it's a pretty big change that I'm making so I want to be careful how I implement them. The first room that I want to change over is 9'x5' with about an 8' ceiling. It has 2 3x3 octagonal tables, each with a pair of stacked 315 CMHs. 4 plants per table. I have to consider how I want to implement the new tables and footprint. It's been a long time since I've grown horizontally so I have to adapt to that, as well. That's why I think I'll start with one LED setup for one of the lights in my veg room and see how it works, especially at the fringes. The CMHs put out about 800ppfd at the distance I have them at so that's what my target will be.

 

[exploziv]

I have never done a big comercial grow, but also I wouldn't use a HPS now even if you gave it to me for free. They are simply too inefficient, when you take the spread and penetration and heat and everything into account. The growers that are able to change their ways will love them, those set in same
old way treating them as hids will fail and come back to scare others about leds online.
No matter if you are an old or new grower, to me it seems like there is no escuse to buying a hps in 2022. Maybe it's just a fear of new things or some don't want to evolve or maybe aren't able to, but I think everyone should still try them for a grow or 2 and find out before debating against them.

 

[Three Berries]

I'm lucky to hit lower 70Fs for temps with my LEDs this time of year.

 

[f-e]

ButterflyEffect
A 3x3 light will be a 480w based on typical driver sizes. You may use 350-400 of them.

A decent sodium is 1.7 ppf/w at the lamp, but over half of that reflects off something, before it reaches the plants. A bounce is a 10% loss if you are lucky. The intensity under the lamp keeps your light at a certain distance, which doesn't do the edges of the grow any favours. A grid a sodium measurements might be around here somewhere, but the middle usually wastes light, running low on food, while the edge are lacking light and well fed.

The 315 Philips edged this up to 2.1 ppf/w but still has the same limitations regarding spread.

The better LED fixtures are pushing over 3.0 which is 50% more. It's the spread though... there is no high intensity middle and weak edges. Some plots show this situation still exists, but think about the plots for HIDs. It is very different. Also, the reflector and optic losses are vastly diminished. A good LED isn't just 50% ahead of a HID. Thus, 400w a meter is a lot. 480w is bangin. This is why many 600w lights are rated for 1.44 meters. The common 1.2x1.2 tent. Some rule of thumb says 35w a foot, so 300w might do you. However, you are going for an upgrade. Plus you don't want to be at full power, with low spacing from the canopy. The 480 would be nice.



Regarding ppf/w output, I used lamp ratings. This 1.7/2.1/3.0 isn't including driver losses. Sodium lamps always talked lamp power, with the driver a separate issue. With LED, you buy a unit with the ballast attached. It's overall ppf/w rating looks lower, as ballast losses are in the equation. Typically, a light using 3.0 ppf/w LEDs may have a 2.7 ppf/w (umol/j) overall rating. When I talk of a 480w light, it's a 480w driver, at the output end. These are often sold as 550w lights, because that's at the wall. People like bigger W numbers

 

[ButterflyEffect]

ButterflyEffect
A 3x3 light will be a 480w based on typical driver sizes. You may use 350-400 of them.

A decent sodium is 1.7 ppf/w at the lamp, but over half of that reflects off something, before it reaches the plants. A bounce is a 10% loss if you are lucky. The intensity under the lamp keeps your light at a certain distance, which doesn't do the edges of the grow any favours. A grid a sodium measurements might be around here somewhere, but the middle usually wastes light, running low on food, while the edge are lacking light and well fed.

The 315 Philips edged this up to 2.1 ppf/w but still has the same limitations regarding spread.

The better LED fixtures are pushing over 3.0 which is 50% more. It's the spread though... there is no high intensity middle and weak edges. Some plots show this situation still exists, but think about the plots for HIDs. It is very different. Also, the reflector and optic losses are vastly diminished. A good LED isn't just 50% ahead of a HID. Thus, 400w a meter is a lot. 480w is bangin. This is why many 600w lights are rated for 1.44 meters. The common 1.2x1.2 tent. Some rule of thumb says 35w a foot, so 300w might do you. However, you are going for an upgrade. Plus you don't want to be at full power, with low spacing from the canopy. The 480 would be nice.



Regarding ppf/w output, I used lamp ratings. This 1.7/2.1/3.0 isn't including driver losses. Sodium lamps always talked lamp power, with the driver a separate issue. With LED, you buy a unit with the ballast attached. It's overall ppf/w rating looks lower, as ballast losses are in the equation. Typically, a light using 3.0 ppf/w LEDs may have a 2.7 ppf/w (umol/j) overall rating. When I talk of a 480w light, it's a 480w driver, at the output end. These are often sold as 550w lights, because that's at the wall. People like bigger W numbers

Thanks for the response f-e! I always look forward to your advice.

I'm still trying to grasp a lot of what you're saying here. I'm getting closer for sure. I'm gonna replace my T5 in my veg room with a bar setup. Not sure which one yet. Something in the US for ease. I'll make my decisions from the testing there.

My situation is complex because I have 3 flower rooms and I cannot break continuity, so I have to do it and resolve most of the issues so I don't run out of stock. Remember, I'm trying to go from bare bulb CMH vertical to LED horizontal and I'll have to change everything in between. The biggest advantage for me will be no more screening, which takes at least 10 hours per run and another 3 or so to descreen them at the end. Less AC in the summer and not worrying about temps in the winter are added bonuses. See, I can't run AC in the winter, so I have to come up to the rooms 4 times a day to open and close doors(depending on the room) so it shares the air with the rest of the building. The ACs are window bangers and won't work below 25F(extractor fans are now connected to the AC controller), so for 4 months in the winter I have to do this.

 

[f-e]

Thanks for the response f-e! I always look forward to your advice.

I'm still trying to grasp a lot of what you're saying here. I'm getting closer for sure. I'm gonna replace my T5 in my veg room with a bar setup. Not sure which one yet. Something in the US for ease. I'll make my decisions from the testing there.

My situation is complex because I have 3 flower rooms and I cannot break continuity, so I have to do it and resolve most of the issues so I don't run out of stock. Remember, I'm trying to go from bare bulb CMH vertical to LED horizontal and I'll have to change everything in between. The biggest advantage for me will be no more screening, which takes at least 10 hours per run and another 3 or so to descreen them at the end. Less AC in the summer and not worrying about temps in the winter are added bonuses. See, I can't run AC in the winter, so I have to come up to the rooms 4 times a day to open and close doors(depending on the room) so it shares the air with the rest of the building. The ACs are window bangers and won't work below 25F(extractor fans are now connected to the AC controller), so for 4 months in the winter I have to do this.

A good T5 might be 1.8 ppf/w so is marginally better than a good sodium. I'm not sure anyone would notice though.

ppf/w is a bit slang. It's better for us though. It's the same as umol/j or umol/w. Three ways of saying the same thing. We are looking at lights, an asking " For ever watt of energy I put in this thing, how many useful photons do I get out"
A Mol is a big unit. Lots of individual photons are needed to amount to a Mol. A umol, is 0.000001 Mol. U=micro or millionth. Even then, we are not counting individual photons, which are still numerous. We are looking at something like the atomic weight of them all. I'm not actually sure, as it's chemistry I rarely interact with.
Backing up a bit, as I can feel the heat from here, we need an easier approach to this. A more layman reasoning, is a figure that expresses now much light (photons) we get that are photosynthetically useful (400-700nm, blue to red) coming off the light at a given power. PPF is photosynthetic photon flux. The word flux here, simply refers to passing out of the thing. This is what we are interested in when looking at a light. How many useful (photosynthetic) Photons (bits of light) are coming off the light, at a given power. We have chosen the Watt as a good unit of power.
I hope this goes some way to demystifying PPF/W for some readers (also known as umol/j or umol/w but the number is exactly the same, there is no conversion)

So good sodium gives us 1.7 ppf/w (output per watt, of useful light (measured as millionths of a Mol))
The T5 might have an output of 1.8 ppf/w
The CMH 2.1 ppf/w
The good LED, 3.0 ppf/w

The LED urinates over the sodium lamp from a great height.



Non of this is to be confused with ppfd which isn't a measure of what comes off the lamp. Instead, ppfd is a measure of how much light falls upon a surface. A measure of photon density, and photons thin out as we use a lamp to illuminate larger and larger areas. Spreading the number that left the lamp, thinner and thinner.
ppf=number leaving lamp (stated per watt of power consumed)
ppfd=number hitting a surface


Always pleased to help bud. I just hope I am helping, not confusing the matter

 

[ButterflyEffect]

A good T5 might be 1.8 ppf/w so is marginally better than a good sodium. I'm not sure anyone would notice though.

ppf/w is a bit slang. It's better for us though. It's the same as umol/j or umol/w. Three ways of saying the same thing. We are looking at lights, an asking " For ever watt of energy I put in this thing, how many useful photons do I get out"
A Mol is a big unit. Lots of individual photons are needed to amount to a Mol. A umol, is 0.000001 Mol. U=micro or millionth. Even then, we are not counting individual photons, which are still numerous. We are looking at something like the atomic weight of them all. I'm not actually sure, as it's chemistry I rarely interact with.
Backing up a bit, as I can feel the heat from here, we need an easier approach to this. A more layman reasoning, is a figure that expresses now much light (photons) we get that are photosynthetically useful (400-700nm, blue to red) coming off the light at a given power. PPF is photosynthetic photon flux. The word flux here, simply refers to passing out of the thing. This is what we are interested in when looking at a light. How many useful (photosynthetic) Photons (bits of light) are coming off the light, at a given power. We have chosen the Watt as a good unit of power.
I hope this goes some way to demystifying PPF/W for some readers (also known as umol/j or umol/w but the number is exactly the same, there is no conversion)

So good sodium gives us 1.7 ppf/w (output per watt, of useful light (measured as millionths of a Mol))
The T5 might have an output of 1.8 ppf/w
The CMH 2.1 ppf/w
The good LED, 3.0 ppf/w

The LED urinates over the sodium lamp from a great height.



Non of this is to be confused with ppfd which isn't a measure of what comes off the lamp. Instead, ppfd is a measure of how much light falls upon a surface. A measure of photon density, and photons thin out as we use a lamp to illuminate larger and larger areas. Spreading the number that left the lamp, thinner and thinner.
ppf=number leaving lamp (stated per watt of power consumed)
ppfd=number hitting a surface


Always pleased to help bud. I just hope I am helping, not confusing the matter

You're doing an excellent job of explaining things. Thanks so much. I do have a background in both electronics and general electrical, so I have a pretty good grasp of many things related to this. I wired my entire setup, most of which is 220. It's the ultra specific stuff like ppf that throws me, but you've explained it well.

My T5 doesn't put out as much as it used to as I've replaced half the bulbs with basic LED tubes. It's the second stage in the veg room after a smaller homemade version that takes care of seedlings, clones and young plants. The final stage is a 315 CMH setup vertical with a light mover on a pulley. That's where I change the plants from horizontal to vertical.

My rooms are all perpetual so timing is important and I'm thinking by changing the second stage T5 to a significantly more powerful LED will shave time off of my veg times and help push me into the LED realm. The only thing I'll need to really hammer out is how many plants I'll need when I change over flower rooms to horizontal and how to train them to get at least similar yields to what I'm getting now. FWIW, I'm finally at the point of pulling 5-6 ounces per plant. With 8 plants and 1200W of CMH, it's not terrible but could obviously be better. Still working on the training aspect.

 

[f-e]

That's a good commercial yield I think. I go with 18 per meter as an expectation, but in a production environment, any more than 20 with HID was very respectable. Based on 8 weeks.

LED is much more capable, but it's a bit like learning to grow again. I would do a table at a time, so you can incrementally learn to accommodate the changes. The environment change doing them all together, would likely leave you playing catch up constantly. It's vastly different when you obviously have a well tuned environment to re-establish with the new lighting. It will most certainly be worth it though.

 

[Mars Hydro Led]

They exorbitant $ and way way way out of line … Nothing personally against you , you’re a paying vendor & here to make money … In my world even the top shelf is only fetching $2400 USA dollars at best & with legal dispensary’s just around the corner the Price is only going to drop … I’m certainly not going to shell out $10,000 to set up a room …that’s bad business..Even if you make it back in one grow …Which takes about three months to complete a cycle …Numbers just don’t add up for me

Yeah, hope there will be a new LED tech that could help decline the light total cost.

 

[Mars Hydro Led]

I have never done a big comercial grow, but also I wouldn't use a HPS now even if you gave it to me for free. They are simply too inefficient, when you take the spread and penetration and heat and everything into account. The growers that are able to change their ways will love them, those set in same
old way treating them as hids will fail and come back to scare others about leds online.
No matter if you are an old or new grower, to me it seems like there is no escuse to buying a hps in 2022. Maybe it's just a fear of new things or some don't want to evolve or maybe aren't able to, but I think everyone should still try them for a grow or 2 and find out before debating against them.

Totally agree with you. Especially it is 2022 now.

 

[Three Berries]

The problem with using ppf is the consumer measuring it. The 'equivalency' tables to convert I've seen are rather sparse too. More than likely because LEDs will be all over the map I'm guessing.

Something else to consider is the total amount of light per day cycle as some can only process so much.

 

[ButterflyEffect]

That's a good commercial yield I think. I go with 18 per meter as an expectation, but in a production environment, any more than 20 with HID was very respectable. Based on 8 weeks.

LED is much more capable, but it's a bit like learning to grow again. I would do a table at a time, so you can incrementally learn to accommodate the changes. The environment change doing them all together, would likely leave you playing catch up constantly. It's vastly different when you obviously have a well tuned environment to re-establish with the new lighting. It will most certainly be worth it though.

When you say 18 per meter, you mean square meter, correct? I'd be looking to do 3 areas in this 9x5 room, all connected with a 2-foot walk-space in front of them. (Well, one room is, one is 10x5 and the 3rd is 7x5). So, it seems that I'd need to parse out how many plants with how many tops per plant in each 3x3. 54 from that room would be a 35% increase from where I'm at now. That, along with a significant reduction in labor would be remarkable, assuming the quality remains similar. Energy savings would be icing on the cake.

I'll be doing one room at a time as it would be too difficult with how it's set up now versus the way it'll need to be due to going from vertical to horizontal. From what I'm gathering thus far, the lack of UV with the LED can create a situation that lowers the leaf temperature enough which disturbs the VPD balance. The other scenario I gather is from the lights being too close due to the low heat output and that apparently creates issues, although I'm not sure exactly how. I have arduino controllers that control all aspects of the environment and I've refined the code decently over the years, although I really need to figure out how to get a clock into my code so I can run slightly separate routines at night. Maybe even have it do the VPD calcs and adjust the equipment based on those numbers as opposed to just raw Temp and RH. Not that I've had any issues with it but it would be a neat refinement.

When I decide, I'll post some links of the options I'm considering for the first setup, maybe you can let me know what you think.

 

[f-e]

I don't really like the imperial measures. A square meter is 20% bigger than a 3x3 but I was talking HID as that's what you use. I guess you expect 15 in a 3x3 but will see 18 with LED. I have not done a CMH grow so I can't give a definite expectation.
I work with ounces as that's the historic nature of drug dealing. People break them into grams now though, or sell them 10 at a time not 9. It's just a maths thing. People still want oz prices, even on a box. A box is 40oz though, not 36. There is no point making the maths hard, just to pretend 36 is a Kg. Further up we have tons. Purely metric in serious business.
Little story? I give someone a Key they asked for once, and they were on the blower later, moaning it wasn't 36oz. Rolled my eyes a bit, insulted them and took them the rest. As you do.
Some time later, they are back on the blower. "It's half ounce over now"
They thought an oz weighs 28g.
Converting back n forth just introduces errors. One system must be shared by all, and it's Metric. Even in the one single country that seems adamant on using imperial (we know who you are) Metric conversion was done before most of the country was born. Honesty.. It's a bit backwards. Like over 50 years I think.
If people want to feed like a pro, they will be measuring in PPM which is metric. If people want to light like a pro, they will use photon density, which is Metric. If people want to work out the yield in their tent, they need to measure it again. It's going to be metric.
/moaning mode off (for a paragraph at least)

Radiant heat is Infra Red. Things like reptiles have IR heaters. Years ago IR lamps were popular at home, where people would put them on their backs (and burn themselves when they fell)

Recently we have seen a surge in ceramic IR heaters

Or there is the good oll IR stove top

Heat=Red
Ever get that nagging feeling that someone's trying to program you?
Red

That arduino or apple pie stuff is out of my wheelhouse. I did look at them for a timer that could have a typical 8 programs, but where each was actually a different socket. In effect, 8 separate timers, sharing one screen. I didn't look for very long. It seemed the clock program had been written, but took half someones life and wasn't half way to what I needed. Instead, I filled a shelf with discrete parts, that look far from discrete.

I will always look over your projects man. I find you engaging. It's good to talk.


Three Berries
The consumer doesn't measure ppf. It's lamp output. It's not a recommendation, but I have an idea of my lamps efficiency (being about 2.6 ppf/w) and have used a watt meter and simple multiplication (is it ever simple) to assess my lights expected output after taking 8-10% for driver losses. It's probably meaningless, but I have 3 lights over a meter, and just one of them on a power meter (I might need to unplug it for other duties one day, so just have it on one light, not all of them). This meter is saying 130w right now. I know the ballast takes about 10 of them, so 120w makes it to the Leds. Each of the 120w makes 2.6 so I have about 300 umol/s coming from that light. Three lights. I have 900 umol being emitted from my lighting. Trying to cover a meter.

Back to Metric. When we move our light meter about on the canopy, it might say something in the region of 900 minus some losses. If we grid out our meter, each box might say 900. We don't add them together. The meter has looked at our light, and informed us that if what it's seeing, was seen evenly over a meter, then that would be 900 umol/m2. It's not actually a reading of whats falling on the meter, but rather the meters looking at a very small part of an area presumed to be 1 meter.

It's all so messy I had to do the math and testing to prove to myself I understood it. Nowhere seems to give a clear account.

All that aside, all we really need to is see what the number is on the meter, and know some targets. Such as the 400 grow, 600 bloom recipe. With 150 for babies.
I guess you have a lux meter, not a direct measure of ppfd. So want some tables to convert from lux to ppfd. I'm afraid there are non. All lux meters measure daylight with similar accuracy, but under LEDs they all deviate along different paths. You need a table for your meters model number. I made a table (well actually it's a sum) for the cheapest meter on the planet to aid everyone here that wishes to get onboard for $10. I could make it a table for you. I also have the details for a couple of other meters that have been directly compared to a proper plant meter. The best you can do, is $30 on the yellow 88 meter. 881D was it? Migrow's Shane puts one through it's paces in a youtube, using different colour temperature LEDs to really prove it's worth.
I will help you out if I can. What do you have?

 

[exploziv]

I had both implemented rtc and online time sync in my electronics projects, it's really easy. If I would go that route I would do both, keep internet for sync and time set-up, but run the rtc to get time. They all accurate but will drift some seconds a month. Good enaugh to use when there is no internet available or there is a temp. problem with your internet.

 

[ButterflyEffect]

I had both implemented rtc and online time sync in my electronics projects, it's really easy. If I would go that route I would do both, keep internet for sync and time set-up, but run the rtc to get time. They all accurate but will drift some seconds a month. Good enaugh to use when there is no internet available or there is a temp. problem with your internet.

I'm sure I'll get around to figuring out how to get the rtc code in there. Then it'll be as simple as an If/Else as to what program it uses in the sketch. Minor things, I guess. The biggest hurdle I haven't figured out yet is how to connect my controllers to the internet. I know there's ESP32 & ESP8266, but the research I've done so far tells me it's far from simple to integrate them into my Megas. Once, if ever, I get past that I can easily have the data dumped to the PC in the room and from there create a front-end and then alerts.

If you have any pointers, please let me know!

 

[exploziv]

Mega can talk with esp's very well over serial or whatever other method of communication you want. I have some smart home systems that work on a mix of arduinos and esps.

 

[bigtacofarmer]

is your LED still 4 times as $ expensive per 4 x 4 footprint when compared to HPS ? … Lets say a grower is currently running Nine one thousand watt lamps of HPS covering 144 square feet of growing space … If I switched over to LED how many years would it take to break even on the conversion expense before they become economically viable? Taking into consideration the expense of electricity and replacing bulbs? I’ve been running HPS for 25 years…send me your best LED for a single 4x4 footprint And I will do a dedicated side-by-side test thread for you … in all sincerity from “flower power” ( formerly know as Star Crash ) …peace

When I was running 1000 watt HPS I averaged around 1.25 to 1.5 lb per light. When I switched to 700 watt led my weight immediately went up to 2 to 2.25 per light with lots of room in the canopy for improvement. It's not hard to picture squeezing another pound under each light. Also the air conditioning needs went down and I will never have to replace bulbs.

Not exact math but my quick estimate says I can run 4 leds for the cost of running 3 hps and gain approximately 4 lbs. 8 lbs if I get it completely dialed.
Not sure what improvement you could expect switching from vertical hps the way you run them.

 

[ButterflyEffect]

I don't really like the imperial measures. A square meter is 20% bigger than a 3x3 but I was talking HID as that's what you use. I guess you expect 15 in a 3x3 but will see 18 with LED. I have not done a CMH grow so I can't give a definite expectation.
I work with ounces as that's the historic nature of drug dealing. People break them into grams now though, or sell them 10 at a time not 9. It's just a maths thing. People still want oz prices, even on a box. A box is 40oz though, not 36. There is no point making the maths hard, just to pretend 36 is a Kg. Further up we have tons. Purely metric in serious business.
Little story? I give someone a Key they asked for once, and they were on the blower later, moaning it wasn't 36oz. Rolled my eyes a bit, insulted them and took them the rest. As you do.
Some time later, they are back on the blower. "It's half ounce over now"
They thought an oz weighs 28g.
Converting back n forth just introduces errors. One system must be shared by all, and it's Metric. Even in the one single country that seems adamant on using imperial (we know who you are) Metric conversion was done before most of the country was born. Honesty.. It's a bit backwards. Like over 50 years I think.
If people want to feed like a pro, they will be measuring in PPM which is metric. If people want to light like a pro, they will use photon density, which is Metric. If people want to work out the yield in their tent, they need to measure it again. It's going to be metric.
/moaning mode off (for a paragraph at least)

Radiant heat is Infra Red. Things like reptiles have IR heaters. Years ago IR lamps were popular at home, where people would put them on their backs (and burn themselves when they fell)

Recently we have seen a surge in ceramic IR heaters

Or there is the good oll IR stove top


Heat=Red
Ever get that nagging feeling that someone's trying to program you?
Red

That arduino or apple pie stuff is out of my wheelhouse. I did look at them for a timer that could have a typical 8 programs, but where each was actually a different socket. In effect, 8 separate timers, sharing one screen. I didn't look for very long. It seemed the clock program had been written, but took half someones life and wasn't half way to what I needed. Instead, I filled a shelf with discrete parts, that look far from discrete.

I will always look over your projects man. I find you engaging. It's good to talk.


Three Berries
The consumer doesn't measure ppf. It's lamp output. It's not a recommendation, but I have an idea of my lamps efficiency (being about 2.6 ppf/w) and have used a watt meter and simple multiplication (is it ever simple) to assess my lights expected output after taking 8-10% for driver losses. It's probably meaningless, but I have 3 lights over a meter, and just one of them on a power meter (I might need to unplug it for other duties one day, so just have it on one light, not all of them). This meter is saying 130w right now. I know the ballast takes about 10 of them, so 120w makes it to the Leds. Each of the 120w makes 2.6 so I have about 300 umol/s coming from that light. Three lights. I have 900 umol being emitted from my lighting. Trying to cover a meter.

Back to Metric. When we move our light meter about on the canopy, it might say something in the region of 900 minus some losses. If we grid out our meter, each box might say 900. We don't add them together. The meter has looked at our light, and informed us that if what it's seeing, was seen evenly over a meter, then that would be 900 umol/m2. It's not actually a reading of whats falling on the meter, but rather the meters looking at a very small part of an area presumed to be 1 meter.

It's all so messy I had to do the math and testing to prove to myself I understood it. Nowhere seems to give a clear account.

All that aside, all we really need to is see what the number is on the meter, and know some targets. Such as the 400 grow, 600 bloom recipe. With 150 for babies.
I guess you have a lux meter, not a direct measure of ppfd. So want some tables to convert from lux to ppfd. I'm afraid there are non. All lux meters measure daylight with similar accuracy, but under LEDs they all deviate along different paths. You need a table for your meters model number. I made a table (well actually it's a sum) for the cheapest meter on the planet to aid everyone here that wishes to get onboard for $10. I could make it a table for you. I also have the details for a couple of other meters that have been directly compared to a proper plant meter. The best you can do, is $30 on the yellow 88 meter. 881D was it? Migrow's Shane puts one through it's paces in a youtube, using different colour temperature LEDs to really prove it's worth.
I will help you out if I can. What do you have?

Aah yes, the old imperial to metric game. Fun stuff indeed. I thought an ounce was 28.4? I just round up to 30 anyhow. Easier math that way.

Do you think I would need some type of IR heat source? I do have controlled heaters in the rooms but what if the heat from the drivers is enough? Or from the summer heat seeping through? If there's a piece of the puzzle that's absolutely needed, I'd rather suss it out and get it taken care of beforehand.

How do you control your environment? I learned to build and code these things due to limited funds and plenty of time. They've been rock solid for years now. I'm just now making the upgrade to a much more stable temp/humidity sensor.

This is one of my frankentrollers....